1. Field of the Invention
The present invention relates to a substrate strip, particularly to a substrate strip with sides having flanges and recesses.
2. Description of the Related Art
Referring to FIG. 1, a conventional substrate strip 1 comprises five die pads 11, 12 for supporting dice (not shown) to be packaged and five mold gates 13, 14 extending from an edge of the substrate strip 1 to each of the die pads 11, 12 for guiding mold compound into the die pads 11, 12. A first frame 15 is defined between the die pad 11 and the die pad 12. A second frame 16 is formed at a lower lateral side of the die pad 11. A third frame 17 is formed at an upper lateral side of the die pad 11 and near the mold gate 13. The first frame 15, the second frame 16, and the third frame 17 are for positioning and delivering the substrate strip 1.
Referring to FIG. 2, the substrate strip 1 is obtained by cutting a panel 2. A plurality of substrate strips 1 can be arrayed on the panel 2 and then cut therefrom. Only some fixed sizes are for the panel 2, and margins should be kept between the substrate strips arrayed, so that the conventional substrate strips cannot be arrayed most densely on the panel 2 to obtain the most substrate strips. Usually, part of the panel is wasted, for example, in a region shown with dotted lines in FIG. 2.
Therefore, it is necessary to provide an innovative and advanced substrate strip so as to solve the above problem.
One objective of the present invention is to provide a substrate strip with sides having flanges and recesses. The substrate strip is obtained by cutting a panel where a plurality of substrate strips can be arrayed. The substrate strip comprises a plurality of die pads, a first side, and a second side. The die pads are for supporting dice to be packaged. The first side comprises a plurality of first flanges and a plurality of first recesses defined between the first flanges. The second side comprises a plurality of second flanges and a plurality of second recesses defined between the second flanges. The second flanges are formed in the locations corresponding to the first recesses, and the second recesses are formed in locations corresponding to the first flanges. The complementary shapes of the first side and the second side are suitable for arraying the two substrate strips most closely, and the most substrate strips can be arrayed most densely. Accordingly, the most substrate strips can be cut from the panel, and waste of the panel can be avoided. The cost of the panel is enormously slashed and the total cost of manufacture is reduced thereby.